Khan, a five-year-old male White Bengal tiger, looks on inside an open-air cage at the Royev Ruchey zoo in Krasnoyarsk, Russia, October 21, 2016. (Photo by Ilya Naymushin/Reuters)

A West African Slender-snouted Crocodile is pictured in its enclosure at the zoo of Abidjan, Ivory Coast September 9, 2016. (Photo by Luc Gnago/Reuters)

A bride stretches before the event during the “Running of the Brides” race, in Bangkok, Thailand, December 2, 2017. Six hundred of to be brides and their grooms compete a run race aimed to win more than two million baht (61,000 US dollars or 51,000 euro) of wedding package prizes including a pair of white gold diamond rings and honeymoon trip to the Maldives. (Photo by Athit Perawongmetha/Reuters)

People take part in a half naked Santa run in downtown Budapest, Hungary, December 9, 2018. The partakers danced, ran, walked and laughed on the streets of Budapest, while others opted to simply raise money for the chosen charity. Many people had the names of their charities written on their bellies, while others were dressed in full Santa outfits. (Photo by Bernadett Szabo/Reuters)

A three month-old baby gorilla named Hasani sits in the grass March 11, 2009 at the San Francisco Zoo in San Francisco, California. The newborn gorilla was given the name Hasani. Hasani's father, a twenty seven year-old gorilla named Oscar Jonsey, picked between five color coded cantaloupes representing the five name finalists to come up with the newborn's name that was submitted by Amanda VerPloeg of Oskaloosa, Iowa. (Photo by Justin Sullivan/Getty Images)

A newly-born male baby elephant, who so far does not have a name, walks with his mother Temi during his first venture outside at their enclosure at the Tierpark Hellabrun zoo on May 12, 2011 in Munich, Germany. The baby elephant was born at the zoo on May 6. (Photo by Alexander Hassenstein/Getty Images)

A baby hippopotamus lies next to its mother on the first day it was presented to the public at the Zoo Berlin zoo on November 1, 2011 in Berlin, Germany. The baby hippo was born at the zoo on October 23. (Photo by Sean Gallup/Getty Images)

Radin the Sunda pangolin hitches a ride on Nita as their keeper looks on. The elusive and nocturnal Sunda pangolin produces only one or two offspring a year and Radin is the third pangolin baby born in Night Safari since 2011. (Photo by Wildlife Reserves Singapore)